Tagged Questions

Encryption is the process of transforming plaintext using a cipher into ciphertext to make it unreadable to anyone except those possessing the key. Decryption is the process of transforming that ciphertext back into plaintext, using the key.

I want to create a smart house project, and in that i bought some simple
RF modules. Those modules don't support crypto out of the box but i want to connect them to a device that i would program to ...

I have to come up with a design for a cryptography system by combining a block cipher and a stream cipher. I can't seem to come up with anything on my own. Can someone point me in the right direction ...

I am implementing AES-ctr encryption. While encrypting I call dofinal on every 16 bytes of data. When I try to decrypt this data in different chunk size say 32 bytes I get different output (original ...

I took a cryptography class back in college, and now that I am working my 1st career one of the things currently on my plate is coming up with an algorithm to encrypt data before it's placed on the ...

I am doing an assignment on writing own encryption and decryption algorithm..so i come across feistel structure...can someone explain to me why we only use reverse order of key in decrpytion and we ...

I'm starting to play with PGP and I don't understand how if your key pair is RSA
you can encrypt a message for someone whose key is for example ElGamal.
How does the asymmetric key exchange work if ...

Say I want to encrypt the following text: "Today is March the 22nd, 2015". And say want to encrypt 8-byte blocks of data using the following permutation [6,3,0,1,5,7,2,4] to swap characters at those ...

Almost every encryption algorithm is based on a secret key. I wonder when the algorithm is considered safe, does that also imply that I can prefix (or suffix) the key with a known value, as long as ...

I've recently started reading the book "Applied Cryptography" written by Bruce Schneier.
Quite a few times I stumbled across protocols who send the identity outside of the encrypted message (see step ...

while working with Encryption mostly cipher text is always larger the plain text, why isn't that the case when downloading a file using https ? even that compression isn't much used anymore because if ...

My professor stated that permutations which are done repeatedly does not further enhance security than just one permutation. He also stated that fact this applies to consecutive substitutions as well. ...

This may seem like a simple question, but I have just started studying cryptography and I can't seem to find any information on this at all. I am trying to write a "simple" encrypted messenger using ...

As I understand, diffusion property in AES-CBC ensures that one-bit change in plaintext will yield changes in all following blocks in ciphertext upon encryption.
I'm looking for algorithm that will ...

Traditional encryption is weak and no longer be used. They can be easily broken by using frequency analysis is a well-known fact.
But, the frequency analysis often depends on the number of captured ...

I decrypted a file which was encrypted with OpenSSL and AES-128 with the wrong password. Before I noticed it was the wrong password I removed the original file. Is there a possibility to reproduce the ...

Recently someone gave me an algorithm as follows:
XOR = Key XOR Random1 XOR Random2.
They think that in order for someone to extract "Key" from XOR they would need Random1 and Random2.. but looking ...

I've seen some posts and info online, but they are from 2009, 2010, 2011 or 2012, which is 3-6 years ago, which is a very long time. So I'm looking for an up-to-date answer about which of these is the ...

I am trying to find out some disadvantages of ElGamal cryptography but I'm not able to figure out what's wrong with the algorithm. The only one I found is that a known-plain text attack is possible in ...